I have recently moved into the top floor apartment in an old brownstone. My apartment has two radiators which I believe are steam powered. they have one pipe going into them and have outlet valves that hiss. They are tipped on the far end to angle towards the valve and heat the room well.
One of these radiators emits intermittant knocks, every few minutes, at the beginning of the heating cycle. It's as if someone is hitting it with a hammer. Once the hissing starts the knocks subside. It's a pain because it is hard to sleep through.
Does anyone have any ideas what can be done to resolve this? I also tried switching off the radiator while sleeping but the knocks still occur. It almost sounds like switching off the radiator doesn't work as I still hear stuff going on inside the radiator though don't get any heat from it during that time.
Is this something that could be resolved or does one just have to live with this sort of thing?